Questions tagged [procrustes-problem]

The Orthogonal Procrustes Problem is a matrix approximation problem in linear algebra. In its classical form, one is given two matrices, $A$ and $B$, and is asked to find an orthogonal matrix $R$ that most closely maps $A$ to $B$.

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Showing that matrix $Q=UV^T$ is the nearest orthogonal matrix to $A$.

Let $A$ be an $m \times n$ matrix with a singular value decomposition $A=U\Sigma V^T$. Show that the matrix $Q=UV^T$ is the nearest orthogonal matrix to $A$, i.e., $$\min_{Q^TQ=I_{n \times n}} \|A-Q\|_F$$
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Solve least-squares minimization from overdetermined system with orthonormal constraint

I would like to find the rectangular matrix $X \in \mathbb{R}^{n \times k}$ that solves the following minimization problem: $$ \mathop{\text{minimize }}_{X \in \mathbb{R}^{n \times k}} \left\| A X - B \right\|_F^2 \quad \text{ subject to } X^T X =…
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Find a permutation of the rows of a matrix that minimizes the sum of squared errors

I'm struggling with the following problem: Let $A, B \in \mathbb R^{n \times d}$. Denote by $\mathcal{P}$ the set of all possible permutations of the rows of $A$. Find a permutation $\pi \in \mathcal{P}$ that minimizes $$\sum_{i=1}^n\sum_{j=1}^d…
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Orthogonal Procrustes Variant

(author note: this question was also asked on mathoverflow). The orthogonal Procrustes problem seeks a matrix $M$ that minimizes $||AM-B||_F$ subject to $M^TM=I$, where $M$ is $d\times d$ and both $A$ and $B$ are $n\times d$. Geometrically, $M$…
Matt
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Orthogonal Procrustes Problem using the operator norm

If $A, B \in \mathbb{R}^{n \times r}$ are two matrices, the solution to the so-called Orthogonal Procrustes Problem $$\min_{O^TO=I_r} \|AO-B\|$$ is given by the polar factor of $A^TB$ whenever the norm is the Frobenius norm. The minimization here…
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Orthogonal Procrustes Problem

The classical Orthogonal Procrustes Problem is $$\begin{array}{ll} \text{minimize} & \|A\Omega-B\|_{F}\\ \text{subject to} & \Omega'\Omega=I\end{array}$$ where $A$ and $B$ are known matrices. Suppose $A$ is the identity matrix. I would like to…
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Solution to a Procrustes-like Problem

I recently came across the following problem that resembles a Procrustes problem and I wonder if an analytic solution for this problem might exist: $$\underset{(R,\alpha)}{\operatorname{argmin}} ||RAe^{j\alpha W}-B||_F$$ Where $A,B \in \mathbb{C}^{3…
Mantabit
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Optimizing Trace$(Q^TZ)$ subject to $Q^TQ=I$

Let $Z \in \mathbb{R}^{m \times n}$ be a tall matrix ($m > n$). Solve the following optimization problem in $Q \in \mathbb{R}^{m \times n}$ $$\begin{array}{ll} \text{maximize} & \mbox{Tr} \left(Q^T Z \right)\\ \text{subject to} & Q^T Q = I_{n…
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Convexity of the orthogonal Procrustes problem

Given two orthogonal matrices ${\bf{M}} \in {{\Bbb{R}}^{m \times n}}$ and ${\bf{N}} \in {{\Bbb{R}}^{m \times n}}$, there is an orthogonal transformation matrix ${\bf{T}} \in {{\Bbb{R}}^{n \times n}}$ which closely maps ${\bf{M}}$ and…
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Orthogonal (unitary) Procrustes problem (complex matrices)

The orthogonal Procrustes problem can be stated as finding the orthogonal matrix $\Omega$ that maps $A$ most closely to $B$ $$\arg\min_{\Omega}\|A\Omega - B\|_F \quad\mathrm{subject\ to}\quad \Omega^T \Omega=I$$ The solution is well known and found…
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Nearest (in the Frobenius sense) semi-orthogonal matrix

I found a question about finding a nearest semi-orthogonal matrix, but I need to find the nearest semi-orthogonal matrix subject to a slightly different constraint. Given $m \times n$ matrix $M$, $$ \begin{array}{ll} \underset {R \in \Bbb R^{m…
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Find an orthogonal matrix to minimize the norm

Let $A\in \mathbb{R}^{n\times n}$. Find $\overline O$, orthogonal matrix, to minimize $\|A-O\|_F$. That is; $$\min_{O\in O(n)} \|A-O\|_F$$ Where $O(n)$ are the set of orthogonal matrices of $\mathbb{R}^{n\times n}$. $\|\cdot \|_F $ is the Frobenius…
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Variant of orthogonal Procrustes problem

I want to find an anti-symmetric matrix $T$ which minimizes $\|A-e^TBe^{-T}\|^2 + \mu\|T\|^2$, where $A$ and $B$ are symmetric positive definite matrices and the norm is the Frobenius matrix norm. The original orthogonal Procrustes problem is to…
uekstrom
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Find $Q$ in $R_2 = Q^TR_1Q$ where all matrices $R_1, R_2, Q$ are 3x3 rotations

Can we obtain $Q$ in $$R_2 = Q^TR_1Q$$ where $R_1, R_2, Q$ are all 3x3 rotation matrices, $R_1 \ne R2$, and $\operatorname{trace}(R_1)=\operatorname{trace}(R_2)$? I have a problem where $R_1$ and $R_2$ are known. I also have the ground truth of $Q$,…
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How is Procrustes Distance Defined?

How is Procrustes Distance defined between two given datasets? Assume that the datasets each of them having "k" points in "n" dimensions. I couldn't find a proper source anywhere with a mathematical expression. I found some leads, but they are in…
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